The invention relates to a neck block system for securing the neck of an acoustic stringed instrument, such as a guitar, to the body of the instrument.
An acoustic stringed instruments, such as a guitar, typically has two main structural components, a neck and a body. Within the internal cavity of an acoustic guitar there are many structural bracing and support members (braces) which are typically made out of wood. The majority of these braces are thin strips fixed with adhesive to the soundboard or the back of the guitar, and don""t significantly contact the sides. There are two exceptions. At the point where the neck joins the body and at the opposite end of the body cavity where the two side sections join, there are internal blocks which are required to take significant structural loading. These are often referred to as the neck block and the end block. These blocks are typically of a much larger cross-section than the braces that are fixed to the soundboard and back. These blocks are typically machined from various species of wood using jigs and fixtures.
The neck block provides the structural integrity required to fix the neck to the body of the guitar and withstand the forces induced through the string tension. This makes the neck block a critical component in determining the stability of the guitar over time.
Furthermore, the integrity of the join between the neck and the body is critical in accurately and efficiently transmitting vibrations between the neck and the body of the guitar. In addition, the xe2x80x9csetxe2x80x9d, or angle that the neck is fixed to the body can have a huge impact on the performance of the guitar. The neck set can affect tone, intonation (the guitar""s ability to stay in tune with itself as various chords are played up the neck) and structural integrity because it affects the string""s overall tension and the distance of the strings from the top of the body as well as the way they vibrate.
Traditionally, the acoustic guitar""s neck is attached to the neck block of the body of the guitar using a basic mortice and tenon joint or by using a dovetail joint in order to build strength and long term reliability. Machining a neck block requires multiple steps and significant time investment from a skilled craftsman.
Under significant tension from the strings when tuned to pitch (about 150 lbs), the joint where the neck meets the body is under constant tension and susceptible to long term changes in temperature and humidity which negatively affect its long term stability and as such the accuracy of the neck set over time.
As shown in FIG. 1, prior art, companies have tried to increase manufacturing flexibility and strength by introducing bolt-on neck blocks for guitars. The neck 20 is bolted to the neck block 22 by means of one or more bolts 24. Neck block 22 is, in turn, affixed to the front and back panels 26 and the sides of the body 28, usually by an adhesive. Due to the significant tension the neck block must withstand, the size of the block is maximized. In left and right-hand cut-a-way models the block must be subsequently cut down to accommodate the cutaway. Decreasing the size of the neck block, however, decreases its much needed strength.
U.S. Pat. No. 6,051,766 to Taylor provides for different sized spacers in recesses where the neck and body meet and bolts that connect the neck and body. However, this invention relies on an L-shaped neck block and neck. This requires lengthy machining processes on both parts (the neck and the neck block) and does not reduce the fluctuations that the neck is exposed to under different temperature and humidity situations. This neck block system does allow for easier adjustment and repair of the neck set as it changes over time due to fluctuations in temperature and humidity, but does little to increase structural stability.
The present invention provides a neck block system for securing a neck of an acoustic stringed instrument having a hollow body to the body of the acoustic stringed instrument, comprising a substantially hollow neck block having an open face on a body side of said neck block, a receiving member on a neck wall of said neck block, said receiving member comprising an aperture through said neck wall and said receiving member having member walls projecting inwards from said neck wall, and a plurality of bracing members reinforcing said receiving member to said neck wall of said neck block. The neck block may be a single piece of rigid molded material.
A front wall may project perpendicular from the neck wall of the neck block, and a rear wall may project perpendicular from the neck wall of the neck block. A locating slot on the front wall and a locating slot on the rear wall may be configured for keying with corresponding protrusions located in the body of the stringed instrument. The locating slots may be configured in a T shape. The neck block may have a top wall projecting perpendicular from the neck wall of the neck block, and a bottom wall projecting perpendicular from the neck wall of the neck block. A shoulder on the top wall and a shoulder on the bottom wall may be configured to key with corresponding protrusions located in the body of the stringed instrument. In an embodiment, the bracing members are each arranged perpendicular to the receiving member and perpendicular to the neck wall.
The invention further teaches a binding strip having a heel strip, a wall strip, and a strip key, the heel strip joined lengthwise at a right angle, wherein the neck block has a strip indentation configured to key with the strip key, and the binding strip and neck block are configured such that the neck block system is suitable for any of a right cutaway, a left cutaway or a non-cutaway stringed instrument.
The neck block system may have a dowel member protruding outwardly from the neck wall opposite the receiving member, wherein the dowel member is configured to key with a corresponding aperture located in the neck of the stringed instrument.
A corner shoulder at the corner of the neck wall may be configured for keying with a corresponding body frame in the body of the stringed instrument. In one embodiment, there is a corner shoulder at each corner of the neck wall. In another embodiment, there is a neck wall shoulder located along an edge where the neck wall joins the front wall and a neck wall shoulder located along an edge where the neck wall joins the rear wall and the neck wall shoulders are each configured for keying with a corresponding body frame in the body of the stringed instrument.
The invention also teaches a neck block system for securing the neck of an acoustic stringed instrument having a hollow body to the body of the acoustic stringed instrument, comprising a substantially hollow walled structure, a receiving member projecting inwards from a neck wall of the walled structure, and a plurality of bracing members reinforcing the receiving member to the neck wall of the neck block, wherein the walled structure has an open face on a body side of the neck block. The neck block may be a single piece of rigid molded material. The walled structure may have walls on five sides.
The invention also teaches a neck block system for securing a neck of an acoustic stringed instrument having a hollow body to the body of the acoustic stringed instrument, comprising a walled structure having a neck wall and a dowel member protruding outwardly from the neck wall, the dowel member configured to key with a corresponding aperture located in a neck of the stringed instrument.